Hydrogen replenished lighter-than-air vehicle and method to replenish hydrogen

ABSTRACT

The present invention discloses a lighter-than-air vehicle and a method to replenish hydrogen into the vehicle while the vehicle is in the sky. The lighter-than-air vehicle can use helium or other gases that doesn&#39;t react with hydrogen as lifting gas. Hydrogen will be replenished into the lighter-than-air vehicle while it is still in mid-air. The lighter-than-air vehicles can comprise an aerostat, a hydrogen generator; a water tank and a duct. The present invention can also comprise an aerostat, a compartment, hydrogen generator, a water tank; and a duct. The present invention can also comprise an aerostat, a compartment, and a hydrogen storage alloy device. The present invention can also comprise an aerostat and a hydrogen storage alloy device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit to provisional application no.61/521,435, filed on Aug. 9, 2011, which is incorporated by referenceherein in its entirety.

FIELD OF INVENTION

The present invention relates generally to aerostats, and moreparticularly, to the lifting gasses of lighter-than-air vehicles, and ameans of replenishing hydrogen into helium-filled lighter-than-airvehicles while the vehicle is still in the sky.

BACKGROUND

Lighter-than-air vehicles typically are constructed with inflatablefabric envelopes, filled with lighter-than-air lifting gasses. Suchvehicles and can rise up to an altitude of 5,000 meters. Some of themare tethered to the ground by a cable, and many others are self-poweredand can move on their own by some kind of propelling system.Lighter-than-air vehicles include aerostats free balloons, airships, andmoored balloons. Lighter-than-air vehicles are lifted from the groundaerostatically rather than aerodynamically. They are widely used fortelecommunications, radar systems, air traffic management, bordercontrol, environment protection and security. Tethered aerostats havethe capability of providing continuous and non-interrupted service for24 hours a day, 7 days a week under all kind of weather conditions.

Lifting gasses for lighter-than-air vehicles can be any gasses that arelighter than air. Hydrogen, helium, methane, ammonia and hot air are allcapable of being used for aerostatic lift.

Helium is the most commonly used lifting gas for lighter-than-airvehicles. Helium is the second lightest element on earth. It is callednoble gas because it is a colorless, odorless, tasteless, non-toxic,inert, monatomic gas. However, using helium as lifting gas forlighter-than-air vehicles has many drawbacks.

Helium gas leaks from aerostats easily due to its small molecular size.As a result, tethered aerostats need to be refilled periodically to stayup for services. Almost all of today's tethered aerostats have to bebrought to the ground for helium replenishment. Therefore, the durationa tethered aerostat can remain airborne are limited by this necessity.Additionally, another concern using helium as lifting gas is thatdespite its abundance, the supply of helium may be dwindling. Helium isrelatively rare element on earth—only 0.00052% by volume of earth'satmosphere.

Hydrogen was once a quite popular lifting gas used for lighter-than-airvehicles. Hydrogen is the first element in the periodic table. It isalso the lightest and most abundant element on earth. However, hydrogenis highly flammable with the presence of oxygen that a small spark maycause a hydrogen explosion. Hydrogen was nevertheless widely used aslifting gas because it could be mass-produced through a variety ofchemical processes at a low cost.

Methane and ammonia are other alternatives that can be used as liftinggas. Both methane and ammonia are chemical compounds containing atoms ofone element bonded with hydrogen atoms. However, they have much lesslifting power than either hydrogen or helium. Additional, methane hasthe drawback of being an explosive compound, and ammonia is dangerousfor being toxic.

What is needed is a lighter-than-air vehicle that uses lifting gasesthat have helium's lifting ability and hydrogen's abundance in supplywithout the dangerous properties of each of the gases. What is alsoneeded is a means of refilling lighter-than-air vehicle with the liftinggases without having the need to ground the lighter-than-air vehicle.

SUMMARY OF THE INVENTION

It is an aspect of the present invention is to provide means ofreplenishing hydrogen into the helium-filled lighter-than-air vehiclesfrom the vehicle itself to allow it to maintain a long term, continuousmission without the needs to bring aerostat down to ground.

This aspect of the present invention can be obtained by a lighter-than-air vehicle comprising: an aerostat with a pressurized chamber filledwith helium; a hydrogen generator; a water tank; a duct connecting thesaid hydrogen generator to the said water tank.

This aspect of the present invention can also be obtained by alighter-than-air vehicle comprising: an aerostat with a pressurizedchamber filled with helium; a compartment inside the said pressurizedchamber; a hydrogen generator; a water tank; and a duct connecting saidhydrogen generator to the said water tank.

This aspect of the present invention can also be obtained by alighter-than-air vehicle with hydrogen replenishment comprising: anaerostat with a pressurized chamber filled with helium; a compartmentinside said pressurized chamber surrounded by the said helium; and ahydrogen storage alloy device.

This aspect of the present invention can also be obtained by alighter-than-air vehicle with hydrogen replenishment comprising: anaerostat with a pressurized chamber filled with helium; and a hydrogenstorage alloy device.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present device, as well as thestructure and operation of various embodiments of the present device,will become apparent and more readily appreciated from the followingdescription or the preferred embodiments, taken in conjunction with theaccompanying drawing of which;

FIG. 1 is a schematic drawing of an embodiment of the hydrogenreplenished lighter-than-air vehicle in the present invention comprisingan aerostat with a pressurized chamber filled with helium, a hydrogengenerator, a water tank, a duct connecting the said hydrogen generatorto the said water tank.

FIG. 2 is a schematic drawing of another embodiment of the hydrogenreplenished lighter-than-air vehicle in the present invention comprisingan aerostat with a pressurized chamber filled with helium, a compartmentinside the said pressurized chamber, a hydrogen generator, a water tank,and a duct connecting said hydrogen generator to the said water tank.

FIG. 3 is a schematic drawing of another embodiment of a hydrogenreplenished lighter-than-air vehicle in the present invention comprisingan aerostat with a pressurized chamber filled with helium, a compartmentinside said pressurized chamber surrounded by the said helium and ahydrogen storage alloy device.

DETAIL DESCRIPTION OF THE INVENTION

This description of the exemplary embodiments is intended to be read inconnection with the accompanying drawings, which are to be consideredpart of the entire written description. In the description, relativeterms such as “lower,” “upper,” “horizontal,” “vertical,”, “above,”“below,” “up,” “down,” “top” and “bottom” as well as derivative thereof(e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should beconstrued to refer to the orientation as then described or as shown inthe drawing under discussion. These relative terms are for convenienceof description and do not require that the apparatus be constructed oroperated in a particular orientation. Terms concerning attachments,coupling and the like, such as “connected” and “interconnected,” referto a relationship wherein structures are secured or attached to oneanother either directly or indirectly through intervening structures, aswell as both movable or rigid attachments or relationships, unlessexpressly described otherwise.

Reference will now be made in detail to the presently preferredembodiments of the invention, examples of which are illustrated in theaccompanying drawings, wherein like reference numerals refer to likeelements throughout.

In FIG. 1, an embodiment of the lighter-than-air vehicle can comprise anaerostat 10 with a pressurized chamber filled with helium, a hydrogengenerator 20, a water tank 30, a duct 40 connecting the said hydrogengenerator to the said water tank. The aerostat 10 is filled with helium.The said hydrogen generator 20 is attached below the aerostat 10. Thehydrogen generator 20 can further comprise a blower and control valve(not shown in figure). The said water tank 30 is attached below theaerostat 10, and the water tank 30 can comprise an atmospheric watergenerator (not shown in figure). There are two ways to provide water forthe hydrogen generator 20. The first way is to store water in the watertank 30 as a payload before the aerostat 10 is lifted. Another way is tocollect water from the ambient air by the atmospheric water generator,which is commercially available on the market. A duct 40 connects thewater tank 30 to the hydrogen generator 20.

In this embodiment, when the pressure of helium gas inside the aerostat10 is reduced to a certain level, a pressure sensor (not show in figure)inside the aerostat 10 will trigger the signal to start the hydrogengenerator 20, which in turn open the control valve to send a burst ofhydrogen gas to replenish the helium filled aerostat 10 until thepressure sensor send a feedback signal to stop the hydrogen generator 20and close the control valve.

When hydrogen is mixed with oxygen in proportion 2:1, or if thevolumetric share of air in the mix exceeds 25%., the resulting gas canbe explosive thus dangerous to use for a lighter-than-air vehicle.Helium is a noble gas which does not react with other element.Therefore, when helium and hydrogen are mixed together, the helium atomswill stable without reaction with the hydrogen atoms, and the hydrogenatoms will join to form H₂. As a result, the aerostats will bereplenished with hydrogen extending the duration that thelighter-than-air vehicle will stay in the sky.

There are a variety of ways to produce hydrogen. One simple way toproduce hydrogen is by the electrolysis of water. Electrolysis of wateris the decomposition of water (H₂O) into oxygen (O₂) and hydrogen gas(H₂) due to an electric current being passed through the water. Thehydrogen generator will draw water from the water tank 30 through theduct 40 and generate hydrogen gas through electrolysis. The resultingoxygen gas will be release into the surround environment. The resultinghydrogen gas will be used to replenish the aerostat 10.

In FIG. 2, an embodiment of the lighter-than-air vehicle can comprise anaerostat with a pressurized chamber filled with helium, a compartmentinside the said pressurized chamber, a hydrogen generator, a water tank,and a duct connecting said hydrogen generator to the said water tank.

Instead of blending hydrogen with helium, as shown in FIG. 2, inside theaerostat 10 there is a compartment 50 filled with hydrogen. The heliumsurrounding the hydrogen-filled compartment 50 serves as a safeguard toprevent hydrogen from mixing with air in order to avoid possible hazardssuch as electrical discharge.

In this embodiment, when the pressure of helium gas inside the aerostat10 is reduced to a certain level, a pressure sensor inside the aerostat10 will trigger the signal to start the hydrogen generator 20, then openthe control valve to send a burst of hydrogen gas to the compartment 50until the pressure sensor send a feedback signal to stop the hydrogengenerator 20 and close the control valve.

The helium gas is a preferred choice for the barrier gas because itachieves the double purposes of lifting of the lighter-than-air vehiclesand serving as a non-reactive barrier gas. However, the barrier gas canalso be any inert gas or even a non-reactive liquid as long as theadditional weight of the barrier substance is offset by the increase inlifting power of the hydrogen.

The advantage of have a barrier surrounding the hydrogen-filledcompartment is to reduce hydrogen explosion. Hydrogen is explosive whencombined with oxygen. However, pure hydrogen gas burns out without anexplosion when it comes in contact with a spark.

In FIG. 3, an embodiment of the lighter-than-air vehicle can comprise anaerostat with a pressurized chamber filled with helium, a compartmentinside said pressurized chamber surrounded by the said helium and ahydrogen storage alloy device.

In fuel cell industry, one solution to storage hydrogen is to store theelement in the form of hydride. This method utilizes an alloy that canabsorb and hold large amounts of hydrogen by bonding with hydrogen andforming hydrides. A hydrogen storage alloy is capable of absorbing andreleasing hydrogen.

This embodiment provides an alternative way to provide hydrogen tohelium aerostat 10 by attaching hydrogen storage alloy device 60 toaerostat 10. When the pressure of helium gas inside the aerostat 10shown in the figure is reduced to a certain level, a pressure sensorinside the aerostat 10 will trigger the signal to open the control valveto send a burst of hydrogen gas to a compartment 50 from hydrogenstorage alloy device 60 until the pressure sensor send a feedback signalto stop the release hydrogen from hydrogen storage alloy device 60 andclose the control valve.

1. (canceled)
 2. (canceled)
 3. (canceled)
 4. (canceled)
 5. Alighter-than-air vehicles comprising: an aerostat; a compartment; atleast one hydrogen generator; at least one water tank; and at least oneduct; wherein the said aerostat further comprises a pressurized chamberfilled with helium; wherein the said compartment is a air-tight ballonetlocated inside the pressurized chamber surrounded by said helium;wherein the said hydrogen generator is attached to the aerostat; whereinthe water tank is connected to the aerostat through the duct.
 6. Thelighter-than-air vehicle as recited in claim 5 wherein said water tankfurther comprises at least one atmosphere water generator to collectwater from ambient atmosphere to be stored in the said water tank. 7.The lighter-than-air vehicles as recited in claim 5, wherein said ductis a tube or a pipe.
 8. The lighter than air vehicles of claim 5 whereinsaid hydrogen generator further includes a blower and control valve torelease hydrogen from said hydrogen generator and to replenish hydrogento said compartment.
 9. A lighter-than-air vehicle comprising: anaerostat; a compartment; and at least one hydrogen storage alloy device;wherein the said aerostat further comprises a pressurized chamber filledwith helium; wherein the said hydrogen storage alloy device is attachedto the aerostat; wherein the said compartment is air-tight ballonetlocated inside the pressurized chamber surrounded by said helium. 10.The lighter than air vehicles of claim 9 wherein said hydrogen storagealloy device further comprises a blower and control valve to releasehydrogen from said hydrogen storage alloy and to replenish hydrogen tosaid compartment.
 11. A lighter-than-air vehicle comprising: anaerostat; and at least one hydrogen storage alloy device; wherein thesaid aerostat further comprises a pressurized chamber filled withhelium; wherein the said hydrogen storage alloy device is attached tothe aerostat.
 12. The lighter than air vehicles of claim 11 wherein saidhydrogen storage alloy device further comprises a blower and controlvalve to release hydrogen from said hydrogen storage alloy and toreplenish hydrogen to said compartment.
 13. A method of replenishinghydrogen to a lighter-than-air vehicle in the sky comprising: providingan aerostat comprising a pressurized chamber; attaching at least onehydrogen generator to the aerostat; providing at least one water tank tothe aerostat; and connecting the water tank to the hydrogen generatorthrough at least one duct; and filling the said aerostat with helium;wherein the said hydrogen generator will generate hydrogen by using thewater from the water tank; wherein the hydrogen generated by thehydrogen generator will be blown into the aerostat.
 14. A method ofreplenishing hydrogen to a lighter-than-air vehicle in the skycomprising: providing an aerostat comprising a pressurized chamber;attaching at least one hydrogen generator to the aerostat; placing onecompartment comprising an air-tight ballonet inside the said pressurizedchamber; providing at least one water tank to the aerostat; andconnecting the water tank to the hydrogen generator through at least oneduct; and filling the said aerostat with helium to surround the saidcompartment; wherein the said hydrogen generator will generate hydrogenby using the water from the water tank; wherein the hydrogen generatedby the hydrogen generator will be blown into the said compartment.
 15. Amethod of replenishing hydrogen to a lighter-than-air vehicle in the skycomprising: providing an aerostat; and attaching a hydrogen storagealloy device to the said aerostat; wherein the said hydrogen storagealloy device will release hydrogen into the said aerostat.
 16. A methodof replenishing hydrogen to a lighter-than-air vehicle in the skycomprising: providing an aerostat; placing one compartment comprising anair-tight ballonet inside the said pressurized chamber; and attaching ahydrogen storage alloy device to the said aerostat; filling the saidaerostat with helium to surround the said compartment; wherein the saidhydrogen storage alloy device will release hydrogen into the saidcompartment.